My mother-in-law has some pain issues and has been prescribed different medications. Most didn't help much but there was a relativity new medication they wanted her to try. They advised there were some possible side effects and requested someone be with her day and night for the first few days to see how she was reacting to it. She is 61 years old and widowed. My wife was too busy with work and since no one else was available to be with her day and night I volunteered. I took a week off work and was going to stay with her and report back if I noticed anything out of the ordinary. Her doctor had a talk with me and outlined what to look for and told me what to expect. I was told excessive sexual activity was the big possible side effect. I asked what that actually meant and was told in drug trials the test subjects mostly lost their inhibitions resulting in nudity and public masturbation. The doctor told me not to mention this to anyone, especially my mother-in-law, as it could cause her to subconsciously act in that way. I asked what I was to do if she started doing something like that. I was told to just let her finish what she started so as not to upset her. I mentioned that would be hard to do if we were in a public place. The doctor suggested keeping her at home until we get a full understanding of how the drug would affect her as everyone reacts differently. The doctor did mention that these sexual actions were strong on the first few days of taking the drug but as people adjusted to taking them they reduced. I mentioned if she does anything like this she will be very embarrassed with me seeing her do so. The doctor stated the one thing that was noted in the test subjects was that they didn't recall doing any sexual activity so if she did anything it would only be me that would know about it which is why it best she be kept at home and only with one person.

I went over to her place and was there when she took her first pill. In 20 minutes she suddenly began to remove her clothes and started rubbing herself between her legs. It was strange watching her because the look on her face was no different than usual except she was naked and masturbating with no concern that was she was doing she shouldn't be doing in front of me. I took the advice from her doctor to just let her do what she was doing until finished so I jsu let her continue. I was very shocked and caught off guard when she stopped what she was doing and began trying to pull my pants down. I was so in shock that not only did she actually managed to get them down but managed to take them right off of me. I was a little confused if I should stop her or just let her continue so as not to upset her. As no one but me would know I just let her continue and she took off everything I was wearing. I didn't know what her intention was going to be but with her climbing on top of me I was going to stop it because there was a very remote possibly of what could be coming next. I then reminded myself it could upset her and since no one would know I decided to let her decide how far she wanted to go. She was putting her breasts in my face and told me to suck them. Her pussy was pressed against my cock but that's as far as that seemed to be going. I knew my mother-in-law pretty well and knew she wasn't going any further with that. She began to open mouth kiss me which was very unexpected. She began to rub her pussy against my cock so there was no penetration but it did make me cum. She got very wet and did get off too. We didn't have sex but I still couldn't believe what we had just done.

When she took her next pill the same thing happened. The next day she masturbated in front of me but that was it. By day three her sexual urges subsided and she was basically back to her usual self. I only mentioned to her doctor that she did masturbate for the first couple of days but that was it. I couldn't mention my cock and her pussy were rubbed together cause up both to have a sexual releases.

For what it is worth, the medication has caused her pain has subsided.